TinyUmbrella allows you to take backups of SHSH blobs (ECID SHSH). Hackers have previously figured out a way to use the SHSH blobs to downgrade to older iOS versions even after Apple stopped signing the firmware file.
Even though it is not possible to downgrade to iOS 6.x.x with the SHSH blobs currently due to the changes incorporated by Apple in iOS 6, it is still a good practise for jailbreakers to take a backup of the SHSH blobs.
As always, let us know how it goes.
Via: TinyUmbrella blog